Many automotive fuel systems include a fuel tank for storing fuel that is eventually consumed by an internal combustion engine. A fuel delivery module comprising, among other things, a reservoir and a fuel pump, may be mounted or suspended within the fuel tank through an opening in a fuel tank wall. Oftentimes the fuel delivery module includes a cover or mounting flange mated with the fuel tank opening to close the opening and prevent fuel liquid and fuel vapor form escaping therethrough. Such covers or mounting flanges are mated with the openings with one or more separately mounted seals between the covers or mounting flanges and the openings. To provide an effective seal, the seals must be positioned and retained within close tolerances.